Work feeder for a double disc grinder

ABSTRACT

A work feeder for feeding workpieces of circular cross section between the grinding discs of a double disc grinder is disclosed including a drive roll 15 positioned exteriorly of the grinding discs and adapted to drive the workpieces through a pair of straight guide bars positioned between the grinder discs. The drive roll frictionally engages the workpieces as they are fed into the clearance space between a fixed peripheral guide and the drive roll to drive them forward into the guide bar space and thence through the grinding zone. The drive roll is supported for pivotal and linear adjusting movement to allow a range of workpiece sizes to be accommodated with only a change in the drive roll sizes and a series of adjustments of the drive roll support and guide bars.

' United States Patent [11 Fallon et a1.

[11] 3,803,769 Apr. 16, 1974 ['54] WORKFEEDER FOR A DOUBLE DISC GRINDER [75] Inventors: Herbert J.'Fallon; JackL. Garnett,

. both of Beloit, Wis.

[73] Assignee: The Bendix Corporation, Southfield,

' Mich.

[22] Filed: Apr. 3, 1973 21 Appl. No.: 347,610 P [52] US. Cl 51/112, 51/87 R, 51/116,

, 51/215 HM, 90/21 A [51]. Int. Cl B24b 9/00, B24b 47/02, B24b 7/00 [58] Field of Search. 51/122, 111 R, 215 AR,

51/2 15 HM, 215R, 139, 140, 87 R,.116;

References Cited UNITED STATES PATENTS 1 2,657,504 11/1953 Cadman ..51/112 2,835,085. :5/1950,Manting", .;.51/215'R Primary Examiner Othe11 M. Simpson Attorney, Agent, or Firm-John R. Benefiel [57] ABSTRACT A work feeder for feeding workpieces of circular cross section between the grinding discs of a double disc grinder is disclosed including a drive r011 15 positioned exteriorly of the grinding discs and adapted to drive the workpieces through a pair of straight guide bars positioned between the grinder discs. The drive r011 frictionally engages the workpieces'as they are fed into the clearance space between a fixed peripheral guide and the drive roll to drive them forward into the guide bar space and thence'throu'gh the grinding zone.

The drive roll is supported-for pivotal and linear adjusting movement to allow a range of workpiece sizes to be accommodated with only a change in the drive to sizes and a series of adjustments of the drive roll support and guide bars.

PATENTEUAPR 16 1914 3.8011769 sum 1 or 6.

WaRKP/EcE n79 FEEDER PATENTEDAPR 16 I974 SHEET 2 [IF 6 IJATENTEDAPR 16 I974 SHEET l 0F 6 P NTEBAPR 16 I974 I 3.8 03; 76 9 SHEEI 8 BF 6 FIGB 1 WORK FEEDER FOR A DOUBLE DISC GRINDER BACKGROUND OF THE INVENTION 1. Field of the Invention This invention concerns double disc grinders and more particularly an arrangement for through feeding of articles of circular cross-section between the grinder discs to grind the end surfaces flat and parallel to each other.

2. Description of the Prior Art Prior art work feeders for grinding the ends of workpieces such as bearing rollers have utilized sprocket type feeders which successively engage rollers and force them through a guide extending through two opposed disc grinding wheels to grind the exposed roller ends flat and parallel.

Among the disadvantages of this approach, is the neeessity for accurate matching of the sprocket shape to the roller diameter and spacing to prevent jams. Even if carefully matched, jams will occur if a space opens up or an odd sized roller is encountered, so that expensive and complicated spring overload arrangements must be provided as the positive nature of this drive could cause great damage in the event of a jam. Such occurrencesof course reduce the production rate since the machine is then shut down.

Another approach is the work feeders of the type described in Swiss Pat. Nos. 427,547 and 445,329 which also have been used for such applications as grinding the end surfaces of bearing rollers. In this arrangement a rotary drivev wheel is disposed between the grinding discs with a fixed peripheral guide disposed adjacent thereto to define a semicircular channel. Frictional engagement of the workpieces with the rotary drive wheel causes the workpieces to rotate and advance through the grind zone. A theoretical advantage of this feed arrangementis that theworkpiece is caused to rotate in the grind zone to produce a desirable cross grind action and the feeding engagement is frictional so that slippage can occur in the event of a jam to lessen the incidence of equipment failure and eliminate jam induced shutdowns.

A disadvantage of this approach is found in the location of the drive roll and the guiding of the rollers in the grind zone by means of the drive roll. That is, the circular drive roll (which is relatively large) must be ground very close to square in order to insure proper location of the rollers as they pass through grind zone. This is aggravated by the exposure of the drive roll to the environrnent of the grind zone, i.e., coolant, grit, detritus which would lead to early wear-out of this expensive component. Further, a different drive roll is required for each roller diameter. t

A second disadvantage results from the curved nature of the path through the grinding zone. The grinding load would impose a large back-out load on the' rollerstending to force them into each other to induce heavy scrubbing due to the rotation of the roller. This leads to the need of a separator such as a sprocket to keep the rollers separated, in turn leading to the disadvantages of the sprocket feeders noted above.

This separationof the workpieces also produces a reduction in the thrusting force since each roller is held only by the contact between the disc and fixed guide and is not aided by the frictional engagement with other rollers. Furthermore, the diameter-to-diameter contact which is usually relied on to maintain squareness of the rollers in the grind zone is lost, and only the disc engagement forces are available to prevent cocking of the rollers in reaction to the grinding forces, which is not adequate in many cases.

Another disadvantage occurring from the partially circular path travelled by the workpieces is that is requires a compound setting of the disc angle i.e., a simple angle isset to define a grinding clearance the rollers (workpieces) will travel through the minimum clearance into an increased clearance and back into an area of minimum clearance as they travel towards the front once again. This results in a time consuming and'error prone set up procedure for the grinder discs.

Therefore, it is an object of the present invention to provide a workfeeder of the type described which drives and rotates the workpieces into and through the grind zone with a purely frictional force, but does not require the use of a rotary drive roll in the grind zone, allows the workpieces to be fed through the grind zone in contact with each other to maintain squareness, and does not require the machining of large precision curved components and requires only a simple angle setting of the grinder discs.

A further object is to provide such an arrangement which is relatively easily adjustable to accommodate a rangeof part sizes without requiring a number of expensive replaceable components.

SUMMARY OF THE INVENTION These and other objects of the present invention which will become apparent upon a reading of the following specification and claims is accomplished by an arrangement wherein a drive roll is positioned exteriorly of the grinding discs and adapted to drive the workpieces through a pair of straight guide bars positioned between the grinder discs. The drive roll frictionally engages the workpieces as they are fed into the clearance space between a fixed peripheral guide and the drive roll to drive them forward into the guide bar space and thence through the grinding zone.

The drive roll is supported for pivotal and linear ad'- justing movement to allow several ranges of workpiece sizes to beaccommodated with only'a change in the drive roll sizes and a series of adjustments.

DESCRIPTION OF THE DRAWINGS FIG. 1 is a diagrammatic representation of a side elevational view of an arrangement according to the present invention.

FIG. 2 is a diagrammatic representation of a top view of an arrangement according to the present invention.

FIG. is a side elevational view of an actual embodiment of an arrangement according to the present invention.

FIG. 4 is a top view of the embodiment shown in FIG. 3.

FIG. 5 is a frontal elevational view of the embodiment shown in FIGS. 3 and 4.

FIG. 6 is a view of the section 6--6 taken in FIG. 3.

FIG. 7 is a view of the section 7-7 taken in FIG. 4.

FIG. 8 is a view of the section 88 taken in FIG. 4.

DETAILED DESCRIPTION In the following detailed description certain specific terminology will be utilized for the sake of clarity and a specific embodiment will be described in order to provide a complete understanding of the invention, but it is to be understood that the invention is not so limited and may be practiced in a variety of forms and embodiments.

Referring to the drawings and particularly FIGS. 1 and 2, the arrangement of the present invention includes a rotary drive roll 10, positioned concentrically with respect to a partially circular guide surface 12 formed on a fixed peripheral guide 14, which is also provided with a pair of end guide plates 13 and 15.

The drive roll is provided with a resilient outer layer 16 to produce a friction drive surface which will compress when workpieces 18 are fed from a workpiece feeder 19 into the clearance space 20 defined between the drive roll 10 and surface 12, so that a firm engagement between the drive roll 10 and a number of the workpieces 18 is created.

Drive means 22 is also provided such as an electric or hydraulic motor and speed reducer arrangement (not shown) to rotate the drive roll 10 at the proper an-' gular velocity for the desired feed rate. workpieces 18 exiting the clearance space 20 are guided into a straight exit section of the fixed peripheral guide 14 by means of a stripper bar 24.

Disposed to receive and guide workpieces leaving the exit section are a pair of guide bars 26 and 28 having clearance space 30 therebetween into which the workpieces 18 pass upon leaving the fixed peripheral guide 14. These guide bars 26 and 28 pass between and across the faces of opposed grinding discs 32 and 34, slightly above center. These grinding discs are set at a simple front-to-back convergent angle so as to produce the narrowest clearance at the point of entrance of the workpieces 18.

It can thus be seen that since the grinding discs sweep across the guide bar clearance 30 approximately normally, the grinding load does not directly induce back up loads on the rollers 18, but rather forces them into the guide bar 28. The desired roller 18 spin is induced as they enter the grind zone due to contact with the leading edge of the abrasive discs and the abrasive disc rotation and subsequent grinding forces.

Since the drive roll 16 only drives the rollers 18 and does not guide them under grinding loads it can be made less accurately and of a smaller size, greatly reducing its cost of manufacture. The guide bars on the other hand, being straight may be ground accurately at a rather low cost, and need only be adjusted not replaced to accommodate various diameter rollers (although different length rollers 18 may require replacement of the guide bars.)

It can also be seen that since the drive roll 10 is positioned exteriorly of the grinding discs 32 and 34 it may be isolated from the grinding zone to reduce wear and the incidence of malfunction induced by the presence therein of coolant, grit, and detritus and since the path defined by the clearance space 30 extends straight across the faces of the grinding discs 32 and 34, a simple front to back convergent angle can be used, much simplifying set up operations.

Since the drive roll 10 simultaneously engages a number of the rollers 18, and the rollers 18 remain in diameter-to-diameter contact, the frictional force available for driving the rollers 18 through the zone is much increased over the arrangement wherein the rollers are individually driven through the grind zone.

This diameter-to-diameter contact also is available to maintain roller 18 squareness during movement through the machine.

In order to accommodate a range of workpiece sizes, both in length and diameter a replaceable spacer 36 is provided between the end guide plates 13 and 15 while the drive roll 10 position is adjustable axially (indicated by the arrow in FIG. 2) to recenter the drive roll 10 on different workpiece lengths. While the drive roll 10 will accommodate a range of roller diameters, in order to provide a greater range, the position of the drive roll 10 is also adjustable radially as indicated in FIG. 1, so that by replacing the drive roll 10 with drive rolls of other diameters and adjusting its center position by the radial movement thereof to restore concentricity with surface 12, various ranges of diameter workpieces can be accommodated.

Referring to FIGS. 3-8, an actual embodiment of a work feed arrangement according to the diagrams of FIGS. 1 and 2 is shown.

The basic components are the same as in FIGS. 1 and 2, i.e., a drive roll 38, a fixed peripheral guide 40 having formed thereon a partially circular guide surface 42 positioned concentrically with respect to the drive roll 38 to define an annular clearance space 44 adapted to receive workpieces (rollers 46) so that the drive roll 38 will engage the same and rotate and drive them through the annular clearance space 44. The rollers 46 are guided into the space 48 between a pair of straight guide bars, lower guide bar 50 and upper guide bar 52 by means of right and left hand strippers 54 and 56 (FIGS. 3, 8) having relieved areas 58 and 60 for drive roll 38 clearance so that the rollers 46 are guided out of the annular clearance space 44 into a straight exit section 62 and thence into space 48 between the guide bar 50 and 52. These guide bars 50 and 52 extend straight across the face of a pair of grinding discs (represented in FIG. 3 by the radius 64).

Right and left hand side guides 66 and 68 are provided to maintain the rollers 46 square until they enter the grind zone so that any tendency the rollers have to rock or drift is counteracted. This is carried out in the grind zone by maintaining the rollers 46 in firm contact with each other throughout the movement through the grind zone.

The work feeder from 70 is secured to the grinding machine face (represented in FIG. 3 by line 72).

The drive roll 38 includes an outer resilient layer 74 (FIG. 6) formed of a material such as urethane bonded to steel hub 76. Hub 76 is in turn secured to an integral hub 78 and shaft 80 rotatably supported in a swing housing 82. Shaft 80 is driven through a speed reducer 84 secured to the swing housing 82. The reducer input shaft 86 is preferably driven by an electric motor, belt and pulley combination (not shown) to produce rotation of the drive roll 38 at the proper speed for the desired feed rate.

Since a fairly wide range of roller 46 sizes both in diameters and length are normally required to be ground with the use of a single machine, it is desirable that the work feeder components be adjustable to accommodate this range of roller 46 sizes.

These adjustments include radial and axial move ment of the drive roll 38 position, i.e., radially to maintain concentricity with surface 42 when the drive roll 38 is changed for one of a different diameter (to accommodate a change in roller 46 diameter range) and laterally to recenter the drive roll 38 when a roller of different length is being ground.

The radial adjustment is accomplished by pivota support of the swing housing 80 on pivot shaft 88, located to swing the housing normally to surface 42, the pivot shaft 88, in turn supported on ears 90, 92 integral with a slide housing 94.

The angular position of the swing housing 80 about the pivot shaft 80 is controlled by threaded shaft 96 threadably engaging a threaded opening 98 found in a second pivot shaft 100 carried by ears 102, 104 integral with swing housing 80.

Threaded shaft 96 is rotated by means of hand wheel 106 coupled to threaded shaft 96 by coupling 108 rotatably supported in pivot support shaft 110 rotatably supported in ears 112, 114. The pivot shafts 100 and 110 by. rotating as angular adjustments are carried out allowing the continued alignment of the threaded shaft 96 with the openings in the pivot shafts 100, 110 as the adjustments are carried out; w

The axial or side-to-side adjustment is accomplished by sliding-support of slide housing 94 on way 116 fixed to the frame 70. A threaded adjustment shaft 118 threadedly engaging an extension block 120 fixed to slide housing 94 and rotated by handwheel 122 produces the axial adjustment by moving the entire assembly of the swing housing 80 supported in the slide housing 94 along the way 116 to thereby adjust the axial position of the drive roll 38. p

The guide bar spacing is adjusted by rotation of a threaded shaft 124 (FIGS. .3 and 7) with a ratchet wrench 126 to raise or lower the upper guide bar 52 which is supported by a right angle block 128 and stud 130.

In and out adjustments are made by adjustments of nuts 132, 134 on stud 130 and shaft 136, respectively which seat the upper and lower guide bars 52, 50. Similar arrangements are provided at the other ends of the guide bars 52, 50.

The-position of the right hand side guide 66 is later ally adjustable to accommodate different roller lengths by insertion of varying width spacers 138 at the points at which it is bolted to the fixed peripheral guide 40.

The right and left hand strippers 54.and 56 are adjustable up and down by means of studs 140, l42'and bolts 144, 146, 148, 150, while theright hand stripper is adjustable in and out by virtue of being fastened to the right .hand side guide.

Accordingly, it can be seen that a range of roller diameters and lengths can be accommodated with a single drive roll and by replacement of the drive roll alone a quite extensive range of diameters may be accommodated at the same time this component is relatively easy to manufacture.

Many variations of this concept are of course possible within the scope of the present invention.

I claim:

1. A work feeding arrangement for feeding roller type workpieces through a double disc grinder of the type having a pair of grinding discs disposed opposite each other with a clearance space therebetween comprising:

a pair of guide bars extending between said grinding discs and positioned to define a linear clearance space extending across said grinding discs;

a drive roll positioned exteriorly of said grinding discs;

means for rotating said drive roll;

a peripheral guide having a partially circular surface 1 formed thereon positioned concentrically with respect to said drive roll to define a clearance space therebetween;

workpiece feeder means for feeding said roller type workpieces into said clearance space between said drive roll and said peripheral guide;

means directing workpieces advanced by rotation of said drive roll through the clearance space between said drive roll and peripheral guide into the linear clearance space between said guide bars, whereby said workpieces are forced through the space between said grinding discs by said drive roll rotation.

2. The arrangement of claim 1 wherein said drive roll is formed with a'resilient outer layer, whereby workpieces fed into said clearance space between said drive roll and peripheral guides may compress said resilient outer layer to tween.

3. The arrangement of'claim 1, including means pivotally mounting said drive roll for radial adjustment with respect to said peripheral guide whereby said drive roll radial position may be adjusted to accommodate a greater range of workpiece diameters.

4. The arrangement of claim 3 wherein said means pivotally mounting said drive roll includes a swing housing in which said drive roll is rotatably mounted, and means pivotally mounting said swing housing including a slide frame on which said swing housing is pivotally mounted and wherein said arrangement further includes means mounting said slide frame for adjustable axial movement, whereby said drive roll position may be adjusted axially to accommodate a greater range of workpiece lengths.

insure frictional engagement therebe- 

1. A work feeding arrangement for feeding roller type workpieces through a double disc grinder of the type having a pair of grinding discs disposed opposite each other with a clearance space therebetween comprising: a pair of guide bars extending between said grinding discs and positioned to define a linear clearance space extending across said grinding discs; a drive roll positioned exteriorly of said grinding discs; means for rotating said drive roll; a peripheral guide having a partially circular surface formed thereon positioned concentrically with respect to said drive roll to define a clearance space therebetween; workpiece feeder means for feeding said roller type workpieces into said clearance space between said drive roll and said peripheral guide; means directing workpieces advanced by rotation of said drive roll through the clearance space between said drive roll and peripheral guide into the linear clearance space between said guide bars, whereby said workpieces are forced through the space between said grinding discs by said drive roll rotation.
 2. The arrangement of claim 1 wherein said drive roll is formed with a resilient outer layer, whereby workpieces fed into said clearance space between said drive roll and peripheral guides may compress said resilient outer layer to insure frictional engagement therebetween.
 3. The arrangement of claim 1, including means pivotally mounting said drive roll for radial adjustment with respect to said peripheral guide whereby said drive roll radial position may be adjusted to accommodate a greater range of workpiece diameters.
 4. The arrangement of claim 3 wherein said means pivotally mounting said drive roll includes a swing housing in which said drive roll is rotatably mounted, and means pivotally mounting said swing housing including a slide frame on which said swing housing is pivotally mounted and wherein said arrangement further includes means mounting said slide frame for adjustable axial movement, whereby said drive roll position may be adjusted axially to accommodate a greater range of workpiece lengths. 